Bug Description

For accessibility support, the workspace switcher needs to support the following. Goal would be to do everything via keyboard.
1) hot key to activate switcher (should match unity-3d which I believe is super-w)
2) first window in first workspace focused
3) tab or arrow key navigate between windows on workspace and then BETWEEN workspaces
4) enter key should exit switcher and activiate focused window
5) ESC exit the switcher without changing workspace

A few corrections:
- unity-3d hotkey for spread is super-s. hotkey to show all windows is super-w
- in unity-3d in the spread, you can only navigate between workspaces (not windows) by using the arrow keys. this should be our goal as well. That is 3) above should allow navigation between workspaces (not windows) and enter should show that workspace.